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991.
Chrétien F Servan J Elghozi D Fontaine B Brion F Ereau T Chesneau AM Hénin D Gray F Duclos H 《Revue neurologique》2001,157(2):178-186
This paper reports the clinico-pathological data in a French family with orthochromatic leukodystrophy. The parents were first cousins and had seven children. Among those, two sisters and one brother presented with neurological signs, with onset around the 5(th) decade, including a dementing syndrome of frontal type, a tetrapyramidal syndrome, seizures, and, in one sibling, a cerebellar syndrome. CT scan or MRI showed diffuse involvement of the white matter. The neurological signs worsened progressively leading to death within 11 and 22 months. Neuropathological examination was performed in two cases. It revealed characteristic orthochromatic leukodystrophy. In one case, the presence of pigmented macrophages and astrocytes was suggestive of Van Bogaert and Nyssen disease. However there were some atypical features including the absence of pigmented cells in the second case whose clinical course was shorter, and the cavitary appearance of the white matter changes with a relative increase in the number of oligodendrocytes raising the issue of a possible link between this condition and cavitary orthochromatic leukodystrophies. 相似文献
992.
Sandberg H Almstedt A Brandt J Gray E Holmquist L Oswaldsson U Sebring S Mikaelsson M 《Thrombosis and haemostasis》2001,85(1):93-100
Recombinant factor VIII SQ (r-VIII SQ), ReFacto, is a recombinant factor VIII product similar to the smallest active factor VIII protein found in plasma-derived factor VIII (p-VIII) concentrates. The protein comprises two polypeptide chains of 80 and 90 kDa and lacks the major part of the heavily glycosylated B-domain i.e. amino acids Gln744 to Ser1637. r-VIII SQ retains six potential glycosylation sites for N-linked oligosaccharides at asparagine residues 41, 239, 582, 1685, 1810 and 2118. We describe a thorough comparison of the characteristics of r-VIII SQ with those of p-VIII. The primary and secondary structures of r-VIII SQ were in good agreement with that of B-domain-deleted p-VIII (p-VIII-LMW) as shown by SDS-PAGE, Western blotting with antifactor VIII antibodies, tryptic mapping, amino acid sequence analysis and circular dichroism spectroscopy. A few divergences also existed. Thus r-VIII SQ was shown to contain a small amount of the single chain primary translation product of 170 kDa and also the product specific sequence of 14 amino acids, the SQ-link, in the C-terminal end of the 90 kDa chain. It was shown that r-VIII SQ had a high specific activity of about 14,000 IU VIII:C/mg as determined by use of a chromogenic substrate assay. The r-VIII SQ protein was comparable to p-VIII forms with a retained B-domain, in terms of potency measured by a chromogenic substrate or a two-stage clotting assay, in interactions with thrombin, and with activated protein C (APC) in combination with Protein S. The ability of r-VIII SQ to participate as a cofactor in factor Xa generation in a mixture of factors IXa and X, phospholipid and calcium was in conformity with that of p-VIII. Furthermore r-VIII SQ had a good binding capacity for phospholipid vesicles and von Willebrand factor (vWF) as shown in gel filtration studies. The same kinetics in binding to von Willebrand factor was found for r-VIII SQ and p-VIII as determined by real-time biospecific interaction analysis (BIA) with use of the BIAcore instrument. The apparent association rate constant was 4 x 10(6) M(-1)s(-1). Two dissociation rate constants were found, 1 X 10(-2)s(-1) and 4 x 10(-4)s(-1). The results extend the present knowledge that the factor VIII B-domain is dispensable for the factor VIII cofactor function in hemostasis. 相似文献
993.
994.
Transition programs in cystic fibrosis centers: perceptions of pediatric and adult program directors
There is a growing population of adults with cystic fibrosis (CF) and a need for development of adult CF programs. Recommendations for transfer of patients to an adult program include a transition program. Our goal was to assess the current status of transition programs in US CF centers. In addition, we sought to determine the problems related to the transfer of patients to adult programs as perceived by CF center program directors. A survey was sent in 1998 to 110 pediatric and 44 adult program directors at CF centers approved by the Cystic Fibrosis Foundation (CFF), with a response rate of 65.5% and 72.7%, respectively: 22.2% of pediatric centers reported having a non-CFF-approved adult program, and 38.9% had no specific adult program. About one fifth of pediatric centers cited lack of an adult CF physician as an impediment to establishing an adult program. Age (82% of programs; mean, 18.5 years), but not marriage (17.1%) or pregnancy (24.8%), was used as a criterion for transfer. Criteria precluding transfer included patient/family resistance (51.4%), disease severity (50.5%), and developmental delay (46.7%). The concept of transfer is introduced to the patient and family at the time of diagnosis in a minority (14%) of programs. Over one half of the patients did not meet the adult team until the time of transfer. Pediatricians reported higher perceived parent, patient, pediatric staff, and adult staff concerns about transition issues than did adult program directors. We conclude that there is a lack of standardized programs for transfer of CF patients from a pediatric to an adult care setting, and that there are differences between pediatric and adult program directors' perceptions of concerns that CF patients, their families, and the medical teams have about transfer. These differences may impede the successful transition of patients into an adult program. 相似文献
995.
996.
Novel erythropoiesis stimulating protein for treatment of anemia in chronic renal insufficiency 总被引:20,自引:0,他引:20
Locatelli F Olivares J Walker R Wilkie M Jenkins B Dewey C Gray SJ;European/Australian NESP Study Group 《Kidney international》2001,60(2):741-747
BACKGROUND: Novel erythropoiesis stimulating protein (NESP) is a glycoprotein with a threefold longer terminal half-life than recombinant human erythropoietin (rHuEPO) in humans. The aim of this study was to determine whether NESP is effective for the treatment of anemia at a reduced dosing frequency relative to rHuEPO in patients with chronic renal failure not yet on dialysis [chronic renal insufficiency (CRI)]. METHODS: This was a multicenter, randomized, open-label study. A total of 166 rHuEPO-naive patients with CRI were randomized in a 3:1 ratio to receive NESP (0.45 microg/kg once weekly) or rHuEPO (50 U/kg twice weekly) administered subcutaneously for up to 24 weeks. Dose adjustments were made as necessary to achieve a hemoglobin response, defined as an increase > or =1.0 g/dL from baseline and a concentration > or = 11.0 g/dL. RESULTS: During the 24-week treatment period, 93% (95% CI, 87 to 97%) of patients receiving NESP and 92% (95% CI, 78 to 98%) of patients receiving rHuEPO achieved a hemoglobin response. The median time to response was seven weeks (range of 3 to 25 weeks) in both groups. After correction of anemia, mean hemoglobin concentrations were maintained within the target range of 11.0 to 13.0 g/dL for the remainder of the 24-week treatment period. The safety profiles of NESP and rHuEPO were similar, and no antibodies were detected to either drug. CONCLUSIONS: These results demonstrate that NESP safely and effectively corrects and maintains hemoglobin concentrations at a reduced dosing frequency relative to rHuEPO in patients with CRI, providing a potential benefit to patients and health care providers. 相似文献
997.
A nested case-control study was undertaken to investigate whether an excess of lympho-haematopoietic cancers in the Australian petroleum industry was associated with benzene exposure. The benzene exposures of the cases and controls were estimated using a quantitative algorithm based largely on exposures measured in the Australian petroleum industry. The algorithm was used to estimate, for each subject, the benzene exposure in parts per million (ppm) for each job held in the industry, and the cumulative exposure in ppm years. Because of the critical importance of the exposure assessment in this design of epidemiological study, particular attention was paid to the reliability of the inputs to the algorithm. The inputs [base estimates (BEs) of exposure and technology-specific exposure modifiers (EMs)] were compared to data from other sources including the occupational hygiene literature. Where such comparison data were available, they were generally found to confirm the values used in the algorithm, although four input values were changed as a result of the validation exercise. The integrity of the task-based algorithm was validated by employing it to calculate the exposures of the tanker drivers in the study and comparing these with measured daily exposure for tanker drivers in the Australian petroleum industry and exposure values found in the occupational hygiene literature. After adjustment for the mix of products carried by the Australian tanker drivers, the estimates from the algorithm were found to be comparable to the measured and literature values. This exercise provided evidence that the exposure assessment for the epidemiological study was reliable and that the results of the study can be used as the basis for evaluating the relationship between exposure to benzene and the risk of lympho-haematopoietic cancer. 相似文献
998.
Is endometrial pre-treatment of value in improving the outcome of transcervical resection of the endometrium? 总被引:1,自引:0,他引:1
The aim of this study was to determine whether or not the use of medical pre-treatment of the endometrium improves the outcome of transcervical resection of the endometrium with regards to long-term operative outcome, histological findings and patient satisfaction. A prospective randomized trial comparing three endometrial pre-treatment agents (danazol, medroxyprogesterone acetate or nafarelin) with no pre-treatment was conducted. The main outcome measures were: (i) thickness of the endometrium and myometrium resected; (ii) histological stage of the endometrium at the time of operation; (iii) the presence or absence of menses and (iv) patient satisfaction 1 year post-operatively. Of the three pre-treatments studied, danazol produced a lower median endometrial thickness than the control, showed the greatest ability to induce atrophy of the endometrial glands and stroma (not statistically significant) and produced the highest rate of amenorrhoea (not different to the control). Danazol and nafarelin produced significantly lower median endometrial thickness than no pre-treatment. There were, however, no significant differences in the rates of amenorrhoea in any of the pre-treatment groups compared with that in the control group. No improvement in clinical outcome or patient satisfaction is conferred by the use of medical pre-treatments if transcervical resection of the endometrium is performed in the proliferative phase of the menstrual cycle. 相似文献
999.
OBJECTIVE: The aim of this study was to investigate the relationship between the expression of the TGF-beta ligands and TGF-beta receptors to the expression of p27(Kip1), a TGF-beta-regulated gene, in endocervical cancer. METHODS: To examine the expression of TGF-beta and p27(Kip1) in malignant transformation of the uterine endocervix, a panel of 23 formalin-fixed and paraffin-embedded human cervical specimens, including 8 with benign endocervical glands, 8 with cervical adenocarcinoma in situ, and 7 with cervical adenocarcinomas, was used. Tissues were immunostained with polyclonal antibodies that react specifically with TGF-beta 1, TGF-beta 2, TGF-beta 3, TGF-beta RI, TGF-beta RII, and p27(Kip1). RESULTS: Immunostaining for TGF-beta 1, TGF-beta 2, TGF-beta 3, TGF-beta RI, TGF-beta RII, and p27(Kip1) was detected in normal endocervix, with the TGF-betas showing weak cytoplasmic staining, while p27(Kip1) showed strong nuclear staining. Expression of TGF-beta increased significantly upon neoplastic transformation with the TGF-beta ligands and receptors showing strong cytoplasmic staining in adenocarcinoma in situ compared to normal endocervix. Interestingly, expression of TGF-beta was lower in adenocarcinoma than in adenocarcinoma in situ, but still significantly higher than in normal endocervix. TGF-beta 2 and TGF-beta 3 showed higher levels of immunostaining than TGF-beta 1 in adenocarcinomas. In contrast, p27(Kip1) protein expression decreased with progressive malignancy, with lower p27(Kip1) protein levels detected in adenocarcinoma than in adenocarcinoma in situ, while normal endocervix showed the highest level of p27(Kip1) protein expression. CONCLUSION: Elevated expression of the TGF-beta ligands and receptors is found in both cervical adenocarcinoma in situ and adenocarcinoma compared to normal endocervix. In contrast, a progressive decrease in p27(Kip1) occurs upon neoplastic transformation of the normal endocervix to cervical adenocarcinoma. These results suggest that neoplastic transformation of the endocervix may be related to dysregulation of TGF-beta and p27(Kip1) seen as an elevation of TGF-beta and a reduction of p27(Kip1) expression that may lead to loss of cell cycle control. 相似文献
1000.